<!-- Licensed under a BSD license. See license.html for license -->
<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
    <title>Three.js - Shadertoy Bleepy Blocks</title>
    <style>
    html, body {
        height: 100%;
        margin: 0;
    }
    #c {
        width: 100%;
        height: 100%;
        display: block;
    }
    </style>
  </head>
  <body>
    <canvas id="c"></canvas>
  </body>
<script type="importmap">
{
  "imports": {
    "three": "../../build/three.module.js"
  }
}
</script>

<script type="module">
import * as THREE from 'three';

function main() {

	const canvas = document.querySelector( '#c' );
	const renderer = new THREE.WebGLRenderer( { antialias: true, canvas } );
	renderer.autoClearColor = false;

	const camera = new THREE.OrthographicCamera(
		- 1, // left
		1, // right
		1, // top
		- 1, // bottom
		- 1, // near,
		1, // far
	);
	const scene = new THREE.Scene();
	const plane = new THREE.PlaneGeometry( 2, 2 );

	const fragmentShader = `
  #include <common>

  uniform vec3 iResolution;
  uniform float iTime;
  uniform sampler2D iChannel0;

  // By Daedelus: https://www.shadertoy.com/user/Daedelus
  // license: Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
  #define TIMESCALE 0.25
  #define TILES 8
  #define COLOR 0.7, 1.6, 2.8

  void mainImage( out vec4 fragColor, in vec2 fragCoord )
  {
    vec2 uv = fragCoord.xy / iResolution.xy;
    uv.x *= iResolution.x / iResolution.y;

    vec4 noise = texture2D(iChannel0, floor(uv * float(TILES)) / float(TILES));
    float p = 1.0 - mod(noise.r + noise.g + noise.b + iTime * float(TIMESCALE), 1.0);
    p = min(max(p * 3.0 - 1.8, 0.1), 2.0);

    vec2 r = mod(uv * float(TILES), 1.0);
    r = vec2(pow(r.x - 0.5, 2.0), pow(r.y - 0.5, 2.0));
    p *= 1.0 - pow(min(1.0, 12.0 * dot(r, r)), 2.0);

    fragColor = vec4(COLOR, 1.0) * p;
  }

  void main() {
    mainImage(gl_FragColor, gl_FragCoord.xy);
  }
  `;
	const loader = new THREE.TextureLoader();
	const texture = loader.load( 'resources/images/bayer.png' );
	texture.minFilter = THREE.NearestFilter;
	texture.magFilter = THREE.NearestFilter;
	texture.wrapS = THREE.RepeatWrapping;
	texture.wrapT = THREE.RepeatWrapping;
	const uniforms = {
		iTime: { value: 0 },
		iResolution: { value: new THREE.Vector3() },
		iChannel0: { value: texture },
	};
	const material = new THREE.ShaderMaterial( {
		fragmentShader,
		uniforms,
	} );
	scene.add( new THREE.Mesh( plane, material ) );

	function resizeRendererToDisplaySize( renderer ) {

		const canvas = renderer.domElement;
		const width = canvas.clientWidth;
		const height = canvas.clientHeight;
		const needResize = canvas.width !== width || canvas.height !== height;
		if ( needResize ) {

			renderer.setSize( width, height, false );

		}

		return needResize;

	}

	function render( time ) {

		time *= 0.001; // convert to seconds

		resizeRendererToDisplaySize( renderer );

		const canvas = renderer.domElement;
		uniforms.iResolution.value.set( canvas.width, canvas.height, 1 );
		uniforms.iTime.value = time;

		renderer.render( scene, camera );

		requestAnimationFrame( render );

	}

	requestAnimationFrame( render );

}

main();
</script>
</html>
